// (c) Copyright Ascensio System SIA 2009-2024
//
// This program is a free software product.
// You can redistribute it and/or modify it under the terms
// of the GNU Affero General Public License (AGPL) version 3 as published by the Free Software
// Foundation. In accordance with Section 7(a) of the GNU AGPL its Section 15 shall be amended
// to the effect that Ascensio System SIA expressly excludes the warranty of non-infringement of
// any third-party rights.
//
// This program is distributed WITHOUT ANY WARRANTY, without even the implied warranty
// of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For details, see
// the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
//
// You can contact Ascensio System SIA at Lubanas st. 125a-25, Riga, Latvia, EU, LV-1021.
//
// The  interactive user interfaces in modified source and object code versions of the Program must
// display Appropriate Legal Notices, as required under Section 5 of the GNU AGPL version 3.
//
// Pursuant to Section 7(b) of the License you must retain the original Product logo when
// distributing the program. Pursuant to Section 7(e) we decline to grant you any rights under
// trademark law for use of our trademarks.
//
// All the Product's GUI elements, including illustrations and icon sets, as well as technical writing
// content are licensed under the terms of the Creative Commons Attribution-ShareAlike 4.0
// International. See the License terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode

import moment from "moment";

export const getCalendarDays = (date: moment.Moment) => {
  const observedDate = moment(date);

  const prevMonthDays = [];
  const currentMonthDays = [];
  const nextMonthDays = [];
  const maxCalendarDays = 42;

  const firstCalendarMonday = observedDate
    .clone()
    .startOf("month")
    .startOf("week")
    .date();

  let yearMonthDate = observedDate.clone().format("YYYY-MM-");

  for (let i = 1; i <= observedDate.clone().daysInMonth(); i += 1) {
    currentMonthDays.push({
      key: yearMonthDate + moment(yearMonthDate + i, "YYYY-MM-D").format("D"),
      value: moment(yearMonthDate + i, "YYYY-MM-D").format("D"),
    });
  }

  if (firstCalendarMonday !== 1) {
    const prevMonthLength = observedDate
      .clone()
      .subtract(1, "months")
      .daysInMonth();

    yearMonthDate = observedDate
      .clone()
      .subtract(1, "months")
      .format("YYYY-MM-");

    for (let i = firstCalendarMonday; i <= prevMonthLength; i += 1) {
      prevMonthDays.push({
        key: yearMonthDate + moment(yearMonthDate + i, "YYYY-MM-D").format("D"),
        value: moment(yearMonthDate + i, "YYYY-MM-D").format("D"),
      });
    }
  }

  yearMonthDate = observedDate.clone().add(1, "months").format("YYYY-MM-");

  for (
    let i = 1;
    i <= maxCalendarDays - currentMonthDays.length - prevMonthDays.length;
    i += 1
  ) {
    nextMonthDays.push({
      key: yearMonthDate + moment(yearMonthDate + i, "YYYY-MM-D").format("D"),
      value: moment(yearMonthDate + i, "YYYY-MM-D").format("D"),
    });
  }

  return { prevMonthDays, currentMonthDays, nextMonthDays };
};
